Compilare: main.cpp: In function 'int main()': main.cpp:82:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < G[1].size(); i++ ) // iterate through all edges of root ~~^~~~~~~~~~~~~ main.cpp:105:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int k = 0; k < G[i].size(); k++ ){ // for all edges from i ~~^~~~~~~~~~~~~